Thread overview
std.stream example
Apr 28, 2008
Me Here
Apr 28, 2008
Simen Kjaeraas
Apr 28, 2008
Gide Nwawudu
April 28, 2008
I just tried to compile the following example ffrom the std.stream docs:

import std.stdio;
import std.stream;

int main (char[][] args) {

    Stream file = new BufferedFile( "myfile" );
    foreach( ulong n, string line; file ) {
        writefln( "line %d: %s", n,line );
    }
    file.close();
    return 0;
}

I'm getting:


fhash.d(31): function std.stream.Stream.opApply (int delegate(ref char[] line)) does not match parameter types (int delegate(ref ulong __applyArg0, ref invariant(char)[] __applyArg1))

fhash.d(31): Error: cannot implicitly convert expression (__foreachbody15) of type int delegate(ref ulong __applyArg0, ref invariant(char)[] __applyArg1) to int delegate(ref ulong n, ref wchar[] line)

Have I got my libraries screwed up?
Or c&p the example incorrectly?
Or is the example just out of date or otherwise screwed?

Cheers, b.



-- 

April 28, 2008
On Mon, 28 Apr 2008 15:36:18 +0200, Me Here <p9e883002@sneakemail.com> wrote:

>
> I just tried to compile the following example ffrom the std.stream docs:
>
> import std.stdio;
> import std.stream;
>
> int main (char[][] args) {
>    Stream file = new BufferedFile( "myfile" );
>     foreach( ulong n, string line; file ) {
>         writefln( "line %d: %s", n,line );
>     }
>     file.close();
>     return 0;
> }
>
> I'm getting:
>
>
> fhash.d(31): function std.stream.Stream.opApply (int delegate(ref char[] line))
> does not match parameter types (int delegate(ref ulong __applyArg0, ref invariant(char)[] __applyArg1))
>
> fhash.d(31): Error: cannot implicitly convert expression (__foreachbody15)
> of type int delegate(ref ulong __applyArg0, ref invariant(char)[] __applyArg1)
> to int delegate(ref ulong n, ref wchar[] line)
>
> Have I got my libraries screwed up?
> Or c&p the example incorrectly?
> Or is the example just out of date or otherwise screwed?
>
> Cheers, b.

Looks like a bug to me. Compiles under 1.029, not under 2.0xx.

-- Simen
April 28, 2008
On Mon, 28 Apr 2008 13:36:18 +0000 (UTC), "Me Here"
<p9e883002@sneakemail.com> wrote:

>
>I just tried to compile the following example ffrom the std.stream docs:
>
>import std.stdio;
>import std.stream;
>
>int main (char[][] args) {
> 
>    Stream file = new BufferedFile( "myfile" );
>    foreach( ulong n, string line; file ) {
>        writefln( "line %d: %s", n,line );
>    }
>    file.close();
>    return 0;
>}
>
>I'm getting:
>
>
>fhash.d(31): function std.stream.Stream.opApply (int delegate(ref char[] line)) does not match parameter types (int delegate(ref ulong __applyArg0, ref invariant(char)[] __applyArg1))
>
>fhash.d(31): Error: cannot implicitly convert expression (__foreachbody15) of type int delegate(ref ulong __applyArg0, ref invariant(char)[] __applyArg1) to int delegate(ref ulong n, ref wchar[] line)
>
>Have I got my libraries screwed up?
>Or c&p the example incorrectly?
>Or is the example just out of date or otherwise screwed?
>
>Cheers, b.

> Or is the example just out of date  ...
Example is wrong.

D1 declares a string as char[], D2 declares it as invariant(char)[]. It does not compile because the line variable being passed to Stream.onApply should be mutable.

So foreach( ulong n, string line; file )  changes to:

foreach( ulong n, char[] line; file ) - or - foreach( ulong n, ref char[] line; file )


Gide